DiscordWebhookOperator - add webhook_endpoint to templated fields

[ttomasz]

Added webhook_endpoint to templated fields in DiscordWebhookOperator.

User might want to leverage templates for that field. In my case I wanted to use token saved in password field of a connection to avoid leaking the token to logs:

send_discord_message_task = DiscordWebhookOperator(
        task_id="send_discord_message",
        http_conn_id="discord_webhook",
        webhook_endpoint="webhooks/{{ conn.discord_webhook.login }}/{{ conn.discord_webhook.password }}",
        message="...",
)

It's possible to overwrite templated fields later but this seems like a good default.

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[boring-cyborg]

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[potiuk]

I rebased to check if the static code was just accidental main merge.

[eladkal]

The test failing is:

Traceback (most recent call last):
  File "/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/bin/black", line 8, in <module>
    sys.exit(patched_main())
  File "/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/lib/python3.7/site-packages/black/__init__.py", line 1423, in patched_main
    patch_click()
  File "/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/lib/python3.7/site-packages/black/__init__.py", line 1409, in patch_click
    from click import _unicodefun
ImportError: cannot import name '_unicodefun' from 'click' (/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/lib/python3.7/site-packages/click/__init__.py)
Traceback (most recent call last):
  File "/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/bin/black", line 8, in <module>
    sys.exit(patched_main())
  File "/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/lib/python3.7/site-packages/black/__init__.py", line 1423, in patched_main
    patch_click()
  File "/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/lib/python3.7/site-packages/black/__init__.py", line 1409, in patch_click
    from click import _unicodefun
ImportError: cannot import name '_unicodefun' from 'click' (/home/runner/.cache/pre-commit/repo9lrx9zpk/py_env-python3/lib/python3.7/site-packages/click/__init__.py)

related to click releasing version 8.1.0
pallets/click#2232
which effect black
psf/black#2964

[eladkal]

It should be fixed by #22599

[boring-cyborg]

Awesome work, congrats on your first merged pull request!